Installation for burning liquid fuel



Nov. '25,.194i. A BARGEBOER j 2,263,913

INSTALLATION FOR BURNING LIQUID FUEL Filed March 7, 1939 ADOLF BAResaor:R

. INVENTOR 31 AITORNEY- UNITED STATES PATENT OFFICE INSTALLATION. FORFUEL Adolf Bargeboer, The Hague, Netherlands I Application March 7,1939, Serial No. 260,263

4 Claims.

At installations for burning liquidfuel with wide range burners of thereturn flow type (as f f. i. U. S. A. Pat. 2,079,430) and where the fuelis supplied to the burners by a high-pressure Q pump, it is commonpractice that the return fuel flows back into the suction lead of thehighpressure pump. 7

In many cases these installations suffer of troubles such as unstableburning, undesirable variations in pressure and, in serious cases, acollapse of the pressure and extinguishing of the flames.

The invention eliminates these troubles completely by supplying the fuelto the high-pressure pump under a positive pressure, while the 4 returnfuel flows into the supply lead at a point where said positive pressureprevails.

This may be understood from the results of research about theabovementioned troubles. It has been shown that these troubles were dueto vapour-lock phenomena of the fuel which contains often high volatilecomponents, especially where the fuel, as in most cases, is pre-heated.

These volatile components are liberated by the vacuum-shocks in theliquid which are caused by the irregularities inthe working of' everypump, while these so liberated gases do not resolve or condenseafterwards. So these phenomena give rise to gas-accumulation at thesuction-side of the high-pressure pump, and so cause irregularities, andunder severe circumstances, break-down of the pump-action.

Now it is clear that by supplying the fuel under pressure to thehigh-pressure pump, these dangerous vacuum shocks cannot arise, and sothe formation of gasis eliminated.

Figs. 1, 2 and 3 give schematically some instances of the invention.

In Fig. 1, the high-pressure pump I (f. i. -20

atm.) supplies a greater quantity of fuel to the burners 2 than isburned. The return (surplus) fuel flows via the non-return valves 3 andleads 4 to the collective return lead 5, which issues into the supplylead 6 and the hot-filter I2 of the high-pressure pump I. Fresh fuel issupplied under pressure (f. i. 1-6 atm.) by the lowpressure pump whichsucks the fuel from the tank 8 via a filter Ia. As low-pressure pumpsare not so liable to shock action they do not give rise to vapour-locks.Moreover, in cases, where the fuel is pre-heated, as generally occurs,the heater II may be inserted between the low-and high-pressure pumps,so that the low-pressure pump does not suck highly heated fuel. This ar-'I heater, and the necessary hot-filter I2, whiclijn other cases have tobe placed in the high-pressure lead due to their flow-resistance, arenow much cheaper due to the fact that they need not resist such a highpressure.

The capacity of the burners may be controlled by a valve I3. This mayalso be done by controlling the capacity of the low-pressure pump I, f.i. by adjusting the valve Id. The two pumps I and I, may be builttogether as two stages of a unit. I

Another method of applying the invention is explained in Fi s. 2 and 3.I

Here the return fuel flows through an injector I5. By the energy of thereturn fuel which enters at considerable pressure through the nozzle I6,the fresh fuel is sucked from the tank I! through pipe I8, and ispressed from the part I5a of the injector under considerable pressurethrough pipe 20, heater I9, lead 20 to the highpressure pump 2|. Thispump supplies the fuel to the lead 22 and the pipes 23 to the burners24. The return fuel flows through leads 25 and the collective returnlead 26 to the injector.

The capacity of the burners may becontrolled in the ordinary way by avalve 21. A far better way is attained by varying the opening of thenozzle I6 f. i. by an adjustable needle 28. By opening the nozzle, morefuel is returned and the capacity of the burners decreases. As with,increasing returned fuel quantity the return pressure decreases inabout the same proportion,

v emcient and simple way.

rangement' has also the advantage that this the energy of the injectorremains approximate 1y constant over thewhole range, and the injectoraction is always sufiicient.

Together with this pressure action and the excellent mixing of the hotreturn fuel with the relative cold fuel from thetank, the deviceeliminates the above mentioned troubles in a very With the lead 29 andthe valve 30 the fuel may be circulated at the starting.

With control valve 3| the-pressure of the highpressure pump I may beregulated.

The surplus fuel of the pump 2| may be returned through the by-passes 32and 33.

If the return fuel from the pump 2| flows through the lead 33, the backflow assists the action of the injector.

In order to prevent inverse fiow from the injector to the tank, a checkvalve 36 is inserted into lead I8 and an emergency suction lead 34 withcheck valve 35 provides the possibility of sucking fuel directly fromthe tank I1.

and a supply lead connecting the pressure side 1o of said injector withsaid pump.

2. An installation, as claimed in claim 1, including means for adjustingthe cross-section of said injector nozzle.

3. An installation, as claimed in claim 1, in-

5 .cluding a by-pass connection between said suction lead and pump and anon-retum valve in said by-pass to prevent back flow of fuel to thesuction lead.

4.;An installation, as claimed in claim 1, including a non-return valvein the suction lead.

. i ADOLF BARGEBOER.

